897 resultados para Transfusion threshold


Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: Nowadays, there are very few studies about massive transfusion in our country. This situation generates the necessity to the elevation of possible new strategies to diminish mortality and its adverse effects. Material and methods: All massive transfusions were evaluated in a retrospective way from October 2010 to October 2012. All diagnosis groups were recorded and the patients were divided into three groups depending on the ratio between packed red blood cells (PRBC) and fresh frozen plasma (FFP) units (ratios ≤2, >2, and without FFP). Their mortality and/or survival were evaluated 30 days after as well as all the factors associated with the event. Results: A total of 69 patients were included (37 trauma patients, 28 gunshot wounds and 4 with lacerated wounds); the groups (ratios ≤2, >2, and no plasma at all) were distributed as follows: 30, 30 and 9 patients each, with an overall mortality rate of 60.8% within 30 days. A lower survival rate (12%) in the no plasma group (P=.015) was found and systolic blood pressure during transfusion had a mean of 67.7 mmHg (P=.012) in this group. Fresh frozen plasma units were 136 and 249 for >2 and ≤2 ratios respectively (P<.01); 85.5% of all patients developed metabolic acidosis during the transfusion, and the number of days in the hospital after the event had a mean of 24.5 days in all patients. Conclusions: High rates of massive transfusion mortality are still being reported in our ield. The use of transfusion strategies contribute to elevate the survival rate in patients with massive transfusion treatment

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Background: The use of sagittal abdominal diameter (SAD) has been proposed for screening cardio-metabolic risk factors; however, its accuracy can be influenced by the choice of thresholds values. Aim: To determine the SAD threshold values for cardio-metabolic risk factors in Mexican adults; to assess whether parallel and serial SAD testing can improve waist circumference (WC) sensitivity and specificity; and to analyze the effect of considering SAD along with WC and body mass index (BMI) in detecting cardio-metabolic risk. Methods: This cross-sectional study was conducted during 2012-2014 in Northeast Mexico (n = 269). Data on anthropometric, clinical, and biochemical measurements were collected. Sex-adjusted receiver-operating characteristic curves (ROC) were obtained using hypertension, dysglycemia, dyslipidemia and insulin resistance as individual outcomes and metabolic syndrome as a composite outcome. Age-adjusted odds ratios and 95% confidence intervals (CI) were estimated using logistic regression. Results: The threshold value for SAD with acceptable combination of sensitivity and specificity was 24.6 cm in men and 22.5 cm in women. Parallel SAD testing improved WC sensitivity and serial testing improved WC specificity. The co-occurrence of high WC/high SAD increased the risk for insulin resistance by 2.4-fold (95% CI: 1.1-5.3), high BMI/high SAD by 4.3-fold (95% CI: 1.7-11.9) and SAD alone by 2.2-fold (95% CI: 1.2.-4.2). Conclusions: The use of SAD together with traditional obesity indices such as WC and BMI has advantages over using either of these indices alone. SAD may be a powerful screening tool for interventions for high-risk individuals.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

An investigation into the stability of metal-insulator-semiconductor (MIS) transistors based on alpha-sexithiophene is reported. In particular, the kinetics of the threshold voltage shift upon application of a gate bias has been determined. The kinetics follow stretched-hyperbola-type behavior, in agreement with the formalism developed to explain metastability in amorphous-silicon thin-film transistors. Using this model, quantification of device stability is possible. Temperature-dependent measurements show that there are two processes involved in the threshold voltage shift, one occurring at Tapproximate to220 K and the other at Tapproximate to300 K. The latter process is found to be sample dependent. This suggests a relation between device stability and processing parameters. (C) 2004 American Institute of Physics.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Les accidents sont la cause la plus fréquente de décès chez l’enfant, la plupart du temps à cause d’un traumatisme cranio-cérébrale (TCC) sévère ou d’un choc hémorragique. Malgré cela, la prise en charge de ces patients est souvent basée sur la littérature adulte. Le mannitol et le salin hypertonique (3%) sont des traitements standards dans la gestion de l’hypertension intracrânienne, mais il existe très peu d’évidence sur leur utilité en pédiatrie. Nous avons entrepris une revue rétrospective des traumatismes crâniens sévères admis dans les sept dernières années, pour décrire l’utilisation de ces agents hyperosmolaires et leurs effets sur la pression intracrânienne. Nous avons établi que le salin hypertonique est plus fréquemment utilisé que le mannitol, qu’il ne semble pas y avoir de facteurs associés à l’utilisation de l’un ou l’autre, et que l’effet sur la pression intracrânienne est difficile à évaluer en raison de multiples co-interventions. Il faudra mettre en place un protocole de gestion du patient avec TCC sévère avant d’entreprendre des études prospectives. La transfusion sanguine est employée de façon courante dans la prise en charge du patient traumatisé. De nombreuses études soulignent les effets néfastes des transfusions sanguines suggérant des seuils transfusionnels plus restrictifs. Malgré cela, il n’y a pas de données sur les transfusions chez l’enfant atteint de traumatismes graves. Nous avons donc entrepris une analyse post-hoc d’une grosse étude prospective multicentrique sur les pratiques transfusionnelles des enfants traumatisés. Nous avons conclu que les enfants traumatisés sont transfusés de manière importante avant et après l’admission aux soins intensifs. Un jeune âge, un PELOD élevé et le recours à la ventilation mécanique sont des facteurs associés à recevoir une transfusion sanguine aux soins intensifs. Le facteur le plus prédicteur, demeure le fait de recevoir une transfusion avant l’admission aux soins, élément qui suggère probablement un saignement continu. Il demeure qu’une étude prospective spécifique des patients traumatisés doit être effectuée pour évaluer si une prise en charge basée sur un seuil transfusionnel restrictif serait sécuritaire dans cette population.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Les accidents sont la cause la plus fréquente de décès chez l’enfant, la plupart du temps à cause d’un traumatisme cranio-cérébrale (TCC) sévère ou d’un choc hémorragique. Malgré cela, la prise en charge de ces patients est souvent basée sur la littérature adulte. Le mannitol et le salin hypertonique (3%) sont des traitements standards dans la gestion de l’hypertension intracrânienne, mais il existe très peu d’évidence sur leur utilité en pédiatrie. Nous avons entrepris une revue rétrospective des traumatismes crâniens sévères admis dans les sept dernières années, pour décrire l’utilisation de ces agents hyperosmolaires et leurs effets sur la pression intracrânienne. Nous avons établi que le salin hypertonique est plus fréquemment utilisé que le mannitol, qu’il ne semble pas y avoir de facteurs associés à l’utilisation de l’un ou l’autre, et que l’effet sur la pression intracrânienne est difficile à évaluer en raison de multiples co-interventions. Il faudra mettre en place un protocole de gestion du patient avec TCC sévère avant d’entreprendre des études prospectives. La transfusion sanguine est employée de façon courante dans la prise en charge du patient traumatisé. De nombreuses études soulignent les effets néfastes des transfusions sanguines suggérant des seuils transfusionnels plus restrictifs. Malgré cela, il n’y a pas de données sur les transfusions chez l’enfant atteint de traumatismes graves. Nous avons donc entrepris une analyse post-hoc d’une grosse étude prospective multicentrique sur les pratiques transfusionnelles des enfants traumatisés. Nous avons conclu que les enfants traumatisés sont transfusés de manière importante avant et après l’admission aux soins intensifs. Un jeune âge, un PELOD élevé et le recours à la ventilation mécanique sont des facteurs associés à recevoir une transfusion sanguine aux soins intensifs. Le facteur le plus prédicteur, demeure le fait de recevoir une transfusion avant l’admission aux soins, élément qui suggère probablement un saignement continu. Il demeure qu’une étude prospective spécifique des patients traumatisés doit être effectuée pour évaluer si une prise en charge basée sur un seuil transfusionnel restrictif serait sécuritaire dans cette population.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The popularity of cloud computing has led to a dramatic increase in the number of data centers in the world. The ever-increasing computational demands along with the slowdown in technology scaling has ushered an era of power-limited servers. Techniques such as near-threshold computing (NTC) can be used to improve energy efficiency in the post-Dennard scaling era. This paper describes an architecture based on the FD-SOI process technology for near-threshold operation in servers. Our work explores the trade-offs in energy and performance when running a wide range of applications found in private and public clouds, ranging from traditional scale-out applications, such as web search or media streaming, to virtualized banking applications. Our study demonstrates the benefits of near-threshold operation and proposes several directions to synergistically increase the energy proportionality of a near-threshold server.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Neo-Dandy was a practice-led research project that explored histories of a quintessential men’s and womenswear garment from across the ages — the formal white dress shirt. The aim was to generate a body of radically new mens’ shirts that, whilst incorporating characteristics normally associated with womenswear, would remain acceptable to male wearers. A detailed study identified a broad spectrum of historical design approaches, ranging from the orthodox man’s shirt to the many variations of the women’s blouse. Within this spectrum a threshold was discovered where the men’s shirt morphed into the woman’s blouse — a ‘design moment’ that appeared to typify the dandy figure (a fashion character who subversively confronts dress norms of their day). The research analysed thousands of archive catwalk images from leading contemporary menswear designers, and of these, only a small number tampered appreciably with the men’s white dress shirt — suggesting a new realm of possibility for fashion design innovation. This led to the creation of a new body of work labelled ‘Neo-Dandy’. Sixty ‘concept shirts’ were produced, with differing styles and varying degrees of detailing, that fitted the brief of being acceptable to male wearers, eminently ‘wearable’ and on a threshold position between menswear and womenswear. These designs were each tested, documented, and assessed in their capacity to evolve the Neo-Dandy aesthetic. Based on these outcomes, a list of key design principles for achieving this aesthetic was identified to assist designers in further evolving this style. The creative work achieved substantial public acclaim with the ‘Neo Dandy Collection’ winning a prestigious Design Institute of Australia Award (Lifestyle category) and being one of four finalists in the prestigious overall field for design excellence. It was subsequently curated into three major Brisbane exhibitions — the ARC Biennial, at Artisan Gallery and the industry leader, the Mercedes Benz Fashion Festival. The collection was also exhibited at the Queensland Art Gallery.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

Neo-Dandy was a practice-led research project that explored histories of a quintessential men’s and womenswear garment from across the ages — the formal white dress shirt. The aim was to generate a body of radically new mens’ shirts that incorporated characteristics normally associated with womenswear, whist remaining acceptable to male wearers. A detailed study identified a broad spectrum of historical design approaches, ranging from the orthodox man’s shirt to the many variations of the women’s blouse. Within this spectrum a threshold was discovered where the men’s shirt morphed into the woman’s blouse — a ‘design moment’ that appeared to typify the dandy figure (a fashion character who subversively confronts dress norms of their day). The research analysed thousands of archive catwalk images from leading contemporary menswear designers, and of these, only a small number tampered appreciably with the men’s white dress shirt — suggesting a new realm of possibility for fashion design innovation. This led to the creation of a new body of work labelled ‘Neo-Dandy’. Sixty ‘concept shirts’ were produced, with differing styles and varying degrees of detailing, that fitted the brief of being acceptable to male wearers, eminently ‘wearable’ and on a threshold position between menswear and womenswear. These designs were each tested, documented, and assessed in their capacity to evolve the Neo-Dandy aesthetic. Based on these outcomes, a list of key design principles for achieving this aesthetic was identified to assist designers in further evolving this style. The creative work achieved substantial public acclaim with the ‘Neo Dandy Collection’ winning a prestigious Design Institute of Australia Award (Lifestyle category) and being one of four finalists in the prestigious overall field for design excellence. It was subsequently curated into three major Brisbane exhibitions — the ARC Biennial, at Artisan Gallery and the industry leader, the Mercedes Benz Fashion Festival. The collection was also exhibited at the Queensland Art Gallery.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

All relevant international standards for determining if a metallic rod is flammable in oxygen utilize some form of “promoted ignition” test. In this test, for a given pressure, an overwhelming ignition source is coupled to the end of the test sample and the designation flammable or nonflammable is based upon the amount burned, that is, a burn criteria. It is documented that (1) the initial temperature of the test sample affects the burning of the test sample both (a) in regards to the pressure at which the sample will support burning (threshold pressure) and (b) the rate at which the sample is melted (regression rate of the melting interface); and, (2) the igniter used affects the test sample by heating it adjacent to the igniter as ignition occurs. Together, these facts make it necessary to ensure, if a metallic material is to be considered flammable at the conditions tested, that the burn criteria will exclude any region of the test sample that may have undergone preheating during the ignition process. A two-dimensional theoretical model was developed to describe the transient heat transfer occurring and resultant temperatures produced within this system. Several metals (copper, aluminum, iron, and stainless steel) and ignition promoters (magnesium, aluminum, and Pyrofuze®) were evaluated for a range of oxygen pressures between 0.69 MPa (100 psia) and 34.5 MPa (5,000 psia). A MATLAB® program was utilized to solve the developed model that was validated against (1) a published solution for a similar system and (2) against experimental data obtained during actual tests at the National Aeronautics and Space Administration White Sands Test Facility. The validated model successfully predicts temperatures within the test samples with agreement between model and experiment increasing as test pressure increases and/or distance from the promoter increases. Oxygen pressure and test sample thermal diffusivity were shown to have the largest effect on the results. In all cases evaluated, there is no significant preheating (above about 38°C/100°F) occurring at distances greater than 30 mm (1.18 in.) during the time the ignition source is attached to the test sample. This validates a distance of 30 mm (1.18 in.) above the ignition promoter as a burn length upon which a definition of flammable can be based for inclusion in relevant international standards (that is, burning past this length will always be independent of the ignition event for the ignition promoters considered here. KEYWORDS: promoted ignition, metal combustion, heat conduction, thin fin, promoted combustion, burn length, burn criteria, flammability, igniter effects, heat affected zone.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

When should a person who has a heart attack not be resuscitated? When should a patient no longer be kept alive on a ventilator, or be provided with food and water by a tube? When should a person not be given a blood transfusion they need to stay alive? The answers to these questions depend on a number of factors including the mental or physical condition of the patient and any wishes they have expressed prior to losing the ability to make this decision, as well as the requirements of good medical practice. This video is a record of a public lecture held on 7 July 2004 by the Faculty of Law at the Queensland University of Technology, in association with the Faculty of Health, the Centre for Palliative Care Research and Education, and Palliative Care Queensland.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

INTRODUCTION Inflammation is a protective attempt to facilitate the removal of damaged tissue and to initiate the healing response in other tissues. However, after spinal cord injury (SCI), this response is prolonged leading to secondary degeneration and glial scarring. Here, we investigate the potential of sustained delivery of pro-inflammatory factors vascular endothelial growth factor (VEGF) and platelet derived growth factor (PDGF) to increase early inflammatory events and promote inflammatory resolution. Method Animal ethics approval was obtained from the Queensland University of Technology. Adult Wistar-Kyoto rats (12-16 weeks old) were subjected to laminectomies and T10 hemisections. Animals were then randomised to treatment (implantation of osmotic pump (Alzet) loaded with 5ug VEGF & 5 ug PDGF) or control groups (lesion control or lesion plus pump delivering PBS). Rats were sacrificed at one month and the spinal cords were harvested and examined by immunohistology, using anti-neurofilament-200(NF200) and anti- ionized calcium binding adapter molecule 1 (Iba1). One way ANOVA was used for statistic analysis. Results At 1 month, active pump-treated cords showed a high level of axonal filament throughout the defects as compared to the control groups. The mean lesion size, as measured by NF200, was 0.47mm2 for the lesion control, 0.39mm2 for the vehicle control and 0.078mm2 for the active pump group. Significant differences were detected between the active pump group and the two control groups (AP vs LC p= 0.017 AG vs VC p= 0.004). Iba-1 staining also showed significant differences in the post-injury inflammatory response. Discussion We have shown that axons and activated microglia are co-located in the lesion of the treated cord. We hypothesise the delivery of VEGF/PDGF increases the local vessel permeability to inflammatory cells and activates these along with the resident microglia to threshold population, which ultimately resolved the prolonged inflammation. Here, we have shown that maintaining the inflammatory signals for at least 7 days improved the morphology of the injured cord. Conclusion This study has shown that boosting inflammation, by delivery VEGF/PDGF, in the early phase of SCI helps to reduce secondary degeneration and may promote inflammation resolution. This treatment may provide a platform for other neuro-regenrative therapies.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

A low-cost test bed was made from a modified heavy vehicle (HV) brake tester. By rotating a test HV’s wheel on an eccentric roller, a known vibration was imparted to the wheel under test. A control case for dampers in good condition was compared with two test cases of ineffective shock absorbers. Measurement of the forces at the bearings of the roller provided an indication of the HV wheel-forces. Where the level of serviceability of the shock absorbers varied, differences in wheel load provided a quality indicator corresponding to a change of damper characteristic. Conclusions regarding the levels of damper maintenance beyond which HV suspensions cause road damage and dynamic wheel forces at the threshold of tyre wear at which HV shock absorbers are normally replaced are presented.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

In the design of tissue engineering scaffolds, design parameters including pore size, shape and interconnectivity, mechanical properties and transport properties should be optimized to maximize successful inducement of bone ingrowth. In this paper we describe a 3D micro-CT and pore partitioning study to derive pore scale parameters including pore radius distribution, accessible radius, throat radius, and connectivity over the pore space of the tissue engineered constructs. These pore scale descriptors are correlated to bone ingrowth into the scaffolds. Quantitative and visual comparisons show a strong correlation between the local accessible pore radius and bone ingrowth; for well connected samples a cutoff accessible pore radius of approximately 100 microM is observed for ingrowth. The elastic properties of different types of scaffolds are simulated and can be described by standard cellular solids theory: (E/E(0))=(rho/rho(s))(n). Hydraulic conductance and diffusive properties are calculated; results are consistent with the concept of a threshold conductance for bone ingrowth. Simple simulations of local flow velocity and local shear stress show no correlation to in vivo bone ingrowth patterns. These results demonstrate a potential for 3D imaging and analysis to define relevant pore scale morphological and physical properties within scaffolds and to provide evidence for correlations between pore scale descriptors, physical properties and bone ingrowth.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

By using the Rasch model, much detailed diagnostic information is available to developers of survey and assessment instruments and to the researchers who use them. We outline an approach to the analysis of data obtained from the administration of survey instruments that can enable researchers to recognise and diagnose difficulties with those instruments and then to suggest remedial actions that can improve the measurement properties of the scales included in questionnaires. We illustrate the approach using examples drawn from recent research and demonstrate how the approach can be used to generate figures that make the results of Rasch analyses accessible to non-specialists.